mlxsw: Take tunnel's type into account when searching underlay device

The function __mlxsw_sp_ipip_netdev_ul_dev_get() returns the underlay
device that corresponds to the overlay device that it gets.
Currently, this function assumes that the tunnel is IPv4 GRE, because it
is the only one that is supported by mlxsw driver.

This assumption will no longer be correct when IPv6 GRE support is added,
resulting in wrong underlay device being returned.
Instead, check 'ol_dev->type' and return the underlay device accordingly.

Move the function to spectrum_ipip.c because spectrum_router.c should not
be aware to tunnel type.
Signed-off-by: Amit Cohen <amcohen@nvidia.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/mellanox/mlxsw/spectrum_ipip.c

@@ -384,3 +384,18 @@ int mlxsw_sp_ipip_ecn_decap_init(struct mlxsw_sp *mlxsw_sp)
 
 	return 0;
 }
+
+struct net_device *
+mlxsw_sp_ipip_netdev_ul_dev_get(const struct net_device *ol_dev)
+{
+	struct net *net = dev_net(ol_dev);
+	struct ip_tunnel *tun4;
+
+	switch (ol_dev->type) {
+	case ARPHRD_IPGRE:
+		tun4 = netdev_priv(ol_dev);
+		return dev_get_by_index_rcu(net, tun4->parms.link);
+	default:
+		return NULL;
+	}
+}

drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c

@@ -1055,22 +1055,13 @@ static void mlxsw_sp_vrs_fini(struct mlxsw_sp *mlxsw_sp)
 	kfree(mlxsw_sp->router->vrs);
 }
 
-static struct net_device *
-__mlxsw_sp_ipip_netdev_ul_dev_get(const struct net_device *ol_dev)
-{
-	struct ip_tunnel *tun = netdev_priv(ol_dev);
-	struct net *net = dev_net(ol_dev);
-
-	return dev_get_by_index_rcu(net, tun->parms.link);
-}
-
 u32 mlxsw_sp_ipip_dev_ul_tb_id(const struct net_device *ol_dev)
 {
 	struct net_device *d;
 	u32 tb_id;
 
 	rcu_read_lock();
-	d = __mlxsw_sp_ipip_netdev_ul_dev_get(ol_dev);
+	d = mlxsw_sp_ipip_netdev_ul_dev_get(ol_dev);
 	if (d)
 		tb_id = l3mdev_fib_table(d) ? : RT_TABLE_MAIN;
 	else
@@ -1441,7 +1432,7 @@ mlxsw_sp_ipip_entry_find_by_ul_dev(const struct mlxsw_sp *mlxsw_sp,
 		struct net_device *ipip_ul_dev;
 
 		rcu_read_lock();
-		ipip_ul_dev = __mlxsw_sp_ipip_netdev_ul_dev_get(ol_dev);
+		ipip_ul_dev = mlxsw_sp_ipip_netdev_ul_dev_get(ol_dev);
 		rcu_read_unlock();
 
 		if (ipip_ul_dev == ul_dev)
@@ -1821,7 +1812,7 @@ static void mlxsw_sp_ipip_demote_tunnel_by_ul_netdev(struct mlxsw_sp *mlxsw_sp,
 		struct net_device *ipip_ul_dev;
 
 		rcu_read_lock();
-		ipip_ul_dev = __mlxsw_sp_ipip_netdev_ul_dev_get(ol_dev);
+		ipip_ul_dev = mlxsw_sp_ipip_netdev_ul_dev_get(ol_dev);
 		rcu_read_unlock();
 		if (ipip_ul_dev == ul_dev)
 			mlxsw_sp_ipip_entry_demote_tunnel(mlxsw_sp, ipip_entry);
@@ -4146,7 +4137,7 @@ static bool mlxsw_sp_ipip_netdev_ul_up(struct net_device *ol_dev)
 	bool is_up;
 
 	rcu_read_lock();
-	ul_dev = __mlxsw_sp_ipip_netdev_ul_dev_get(ol_dev);
+	ul_dev = mlxsw_sp_ipip_netdev_ul_dev_get(ol_dev);
 	is_up = ul_dev ? (ul_dev->flags & IFF_UP) : true;
 	rcu_read_unlock();
 

drivers/net/ethernet/mellanox/mlxsw/spectrum_router.h

@@ -226,6 +226,8 @@ static inline bool mlxsw_sp_l3addr_eq(const union mlxsw_sp_l3addr *addr1,
 
 int mlxsw_sp_ipip_ecn_encap_init(struct mlxsw_sp *mlxsw_sp);
 int mlxsw_sp_ipip_ecn_decap_init(struct mlxsw_sp *mlxsw_sp);
+struct net_device *
+mlxsw_sp_ipip_netdev_ul_dev_get(const struct net_device *ol_dev);
 
 extern const struct mlxsw_sp_router_ll_ops mlxsw_sp_router_ll_xm_ops;